Controlling Chirality and Stability of Gold Nanoclusters by PNP Pincer Ligand Diastereomers

The emerging metal nanoclusters with atomically precise
structures
have gained considerable attention because they exhibit promising
applications in various fields and serve as ideal models for studying
the structure–property correlation of nanoparticles. Despite
significant advances, it is still unclear how ligand diastereomers
impact the stability and chirality of metal nanoclusters. In this
work, we systematically studied the construction of gold nanoclusters
using the PNP (PNP = 2,6-bis(1-(diphenylphosphaneyl)ethyl)pyridine)
pincer ligand consisting of multiple stereoisomers. A metastable Au6 skeleton was found to be a key intermediate, which can be
controlled in the aspects of stability and chirality by the PNP ligand
diastereomers to selectively produce Au9(R,R-PNP)4, Au9(S,S-PNP)4, Au9(R,S-PNP)4, Au6(R,S-PNP)2(R,R-PNP),
and Au6(R,S-PNP)2(S,S-PNP) nanoclusters with intriguing properties such as self-sorting
and spontaneous resolution. This work provides a strategy for regulating
the stability and chirality of metal nanoclusters by ligand diastereomers.